Abstract: A storage device includes a memory for storing data in a plurality of logical volumes; a controlling unit for controlling an access to data in accordance with a process comprising the steps of: generating mapping information indicative of a correspondence between logical volume information and recognition information; generating a pseudo logical volume and pseudo logical volume information associated with the pseudo logical volume, the pseudo logical volume being another of the logical volumes; and upon receipt of a command for canceling an assignment of one of the logical volumes to the corresponding recognition information, modifying the mapping information so that recognition information that has been indicative of said one of the logical volumes becomes indicative of the pseudo logical volume information associated with the pseudo logical volume.

Abstract: An allocation apparatus of the present invention provides the mechanism that another logical volume of temporary number is automatically made in the storage system shared with plural servers, when it is recognized that the targeted logical volume is doubly allocated. By the present invention, the data destruction can be prevented by making the target server accessing another logical volume allocated automatically when the double allocation is detected. And the processing of a temporary allocation is continued until the alert message to the effect that the logical volume required from the target server is overlapped in the logical storage area is transmitted to the operator, the allocated another logical volume is approved by the operator, and the cancellation of overlapping allocation is confirmed.

Abstract: An access control device for controlling access from a host system to a plurality of storage areas in a storage system, the access control device includes a memory for storing access management information for the plurality of storage areas, and a controller for managing and monitoring access performed by the host system, the controller monitoring frequency of access by the host system to each of the plurality of storage areas and storing information of the frequency of the access to each of the storage areas in the memory, detecting at least one of the storage areas in which the frequency of the access is less than a predetermined range, and restricting the host system from accessing to the detected storage area.

Abstract: A storage device includes a memory for storing data in a plurality of logical volumes; a controlling unit for controlling an access to data in accordance with a process comprising the steps of: generating mapping information indicative of a correspondence between logical volume information and recognition information; generating a pseudo logical volume and pseudo logical volume information associated with the pseudo logical volume, the pseudo logical volume being another of the logical volumes; and upon receipt of a command for canceling an assignment of one of the logical volumes to the corresponding recognition information, modifying the mapping information so that recognition information that has been indicative of said one of the logical volumes becomes indicative of the pseudo logical volume information associated with the pseudo logical volume.

Abstract: An allocation apparatus of the present invention provides the mechanism that another logical volume of temporary number is automatically made in the storage system shared with plural servers, when it is recognized that the targeted logical volume is doubly allocated. By the present invention, the data destruction can be prevented by making the target server accessing another logical volume allocated automatically when the double allocation is detected. And the processing of a temporary allocation is continued until the alert message to the effect that the logical volume required from the target server is overlapped in the logical storage area is transmitted to the operator, the allocated another logical volume is approved by the operator, and the cancellation of overlapping allocation is confirmed.